So I am selling my iPhone 3gs for 300ish possibly more. I'm planning on getting the iPhone 4 16gb. I signed a new contract last year so it will be am early upgrade. I plan on ordering the phone online and picking up at the AT&T store. I'm just trying to get the prices straight. It will be $400 correct? Will I need any activation fees or anything since I will be upping my contract for another 2 years. Bassically will I need to pay anything more then the 400 for the phone?